1. Field of the Invention
The present invention relates to an ophthalmologic imaging apparatus and, more particularly, to an ophthalmologic imaging apparatus which can image the anterior ocular segment of an eye to be inspected, a method of controlling the same, and a program.
2. Description of the Related Art
Conventionally there has been known a fundus camera which allows an operator to observe and image the fundus and anterior ocular segment of an eye to be inspected. The fundus camera disclosed in Japanese Patent Application Laid-Open No. H04-317628 is configured to cope with imaging of the anterior ocular segment by separating the eye to be inspected from the fundus camera and moving the focus lens, which focuses an imaging plane relative to the eye to be inspected, in the hypermetropic direction.
In addition, the fundus camera disclosed in Japanese Patent Application Laid-open No. 2012-50592 is configured to insert a diopter correction lens and automatically move a focus lens to a predetermined position at the time of anterior ocular segment imaging to facilitate a switchover operation to anterior ocular segment imaging.
The fundus camera disclosed in Japanese Patent Application Laid-Open No. 2012-50592 facilitates operations for most operators. However, when performing anterior ocular segment imaging, different operators may have different regions of main interest, for example, an iris region and an eyelid region. In order to cover ail these needs, it is necessary to set a wide focus adjustable range.
Japanese Patent No. 4430378 discloses the following technique to cope with the wide focus adjustment range for anterior ocular segment imaging in a fundus camera. This technique includes a barrel cam mechanism which converts the rotation of a barrel into linear movement along the optical axis of a focus lens, changes the tilt of the barrel cam between a focus area corresponding to fundus imaging and a focus area corresponding to anterior ocular segment imaging, and increases the tilt of the barrel cam corresponding to the unit rotational angle of the barrel in a focus area corresponding to anterior ocular segment imaging.
According to the technique disclosed in Japanese Patent No. 4430378, however, the use of different focus areas for anterior ocular segment imaging and fundus imaging makes it necessary to ensure a large drive area for the focus lens, resulting in an increase in apparatus size.
In addition, this technique requires the barrel cam, resulting in high cost.
Furthermore, this technique lacks flexibility in terms of focus lens drive amount corresponding to the unit rotational angle of the barrel at the time of anterior ocular segment imaging and at the time of fundus imaging, and hence has the problem of a low degree of freedom in operability setting when performing manual focusing.